Related papers: Galaxy evolution in a complex environment: a multi…
Observations show that galaxies in galaxy clusters are strongly influenced by their environment. There is growing evidence that some galaxies in groups show similar properties to galaxies in clusters, such as redder colours and gas…
The formation of globular clusters remains an open debate. Dwarf starburst galaxies are efficient at forming young massive clusters with similar masses as globular clusters and may hold the key to understanding their formation. We study…
New and archival HST images of the globular cluster systems of 17 relatively nearby galaxies and 6 more distant galaxies have been used to establish the characteristics of GC subpopulations over a range of host galaxy morphological type…
We probe the evolution of globular clusters that could form in giant molecular clouds within high-redshift galaxies. Numerical simulations demonstrate that the large and dense enough gas clouds assemble naturally in current hierarchical…
The formation of ultra-compact dwarf galaxies (UCDs) is believed to be interaction driven, and UCDs are abundant in the cores of galaxy clusters, environments that mark the end-point of galaxy evolution. Nothing is known about the…
We present HI observations of 54 galaxies in the Pegasus cluster. The observations include single dish HI measurements, obtained with the Arecibo telescope for all 54 galaxies in the sample, as well as HI images, obtained with the VLA for…
While the star formation rates and morphologies of galaxies have long been known to correlate with their local environment, the process by which these correlations are generated is not well understood. Galaxy groups are thought to play an…
The nature of compact groups (CGs) of galaxies, apparently so dense that the galaxies often overlap, is still a subject of debate: Are CGs roughly as dense in 3D as they appear in projection? Or are they caused by chance alignments of…
We analyse the K-band Hubble diagram for a sample of brightest cluster galaxies (BCGs) in the redshift range 0<z<1. In good agreement with earlier studies, we confirm that the scatter in the absolute magnitudes of the galaxies is small (0.3…
We present the clump populations detected in 18 lensed galaxies at redshifts 1 to 8.5 within the lensing cluster field SMACS0723. The recent JWST Early Release Observations of this poorly known region of the sky have revealed numerous…
Understanding the astrophysical processes acting within galaxy groups and their effects on the evolution of the galaxy population is one of the crucial topic of modern cosmology, as almost 60% of galaxies in the Local Universe are found in…
We investigate the galaxy populations in seven X-ray selected, intermediate-redshift groups (0.2<z<0.6). Overall, the galaxy populations in these systems are similar to those in clusters at the same redshift; they have large fractions of…
The very high apparent galaxy densities in Hickson compact groups (HCGs) should produce copious amounts of galaxy-galaxy interaction, if these groups are bound dynamical units. I examine the evidence for such interactions in HCG 94, a group…
We compile a sample of spectroscopically- and photometrically-selected cluster galaxies from four high-redshift galaxy clusters ($1.59 < z < 1.71$) from the Spitzer Adaptation of the Red-Sequence Cluster Survey (SpARCS), and a comparison…
The morphology of HII regions around young star clusters provides insight into the timescales and physical processes that clear a cluster's natal gas. We study ~700 young clusters (<10Myr) in three nearby spiral galaxies (NGC 7793, NGC…
We present preliminary results of VLA HI imaging of selected Virgo cluster galaxies. The goal is to study environmental effects on galaxy evolution. Our sample of 41 galaxies is spread throughout the cluster and spans a wide range in star…
The currently available empirical evidence on the star formation processes in the extreme, high-pressure environments induced by galaxy encounters, mostly based on high-resolution Hubble Space Telescope imaging observations, strongly…
(Abridged) The formation and evolution of star cluster populations are related to the galactic environment. Cluster formation is governed by processes acting on galactic scales, and star cluster disruption is driven by the tidal field. In…
HST is very well tailored for observations of extragalactic star clusters. One obvious reason is HST's high spatial resolution, but equally important is the wavelength range offered by the instruments on board HST, in particular the blue…
We use high-precision photometry of red-giant-branch (RGB) stars in 57 Galactic globular clusters (GCs), mostly from the `Hubble Space Telescope (HST) UV Legacy Survey of Galactic globular clusters', to identify and characterize their…